DDR2 version has 16Gb's memory bandwidth -> only playable at 480p (not worth buying , get a wii instead)
DDR3 : 25.6 GB/sec -> HD 720p
But the Nvidia 9000 GT series are really old , most of them are refurbished or 2nd hand productAMD 6570 (you don't need a new PSU for this card and it will blow the 9500GT DDR3)